Hey folks,
I've read everything I can find about insulating the firewall with Fiberfrax and stainless foil, and I'm attempting to follow best practices here, but there are a couple of details that I just haven't been able to glean from all of the incredible research out there. I have two questions.
First - are folks bolting the heater boxes directly to the firewall and then nesting the fiberfrax around it, OR bolting the heater boxes through the foil and fiberfrax? I get that the point of the fiberfrax is to insulate the firewall, and having the heater boxes directly contacting the firewall creates a bunch of heat transfer. BUT, the plans call for sealing the heater boxes, and my worry is that the compressible fiberfrax won't allow a solid seal.
Second, for the oil cooler mount, same sort of question. Are y'all riveting the cooler mount THROUGH the fiberfrax and foil, or, say, shimming it the width of the frax and then riveting through the stainless foil? The former seems ideal, but it feels like riveting through the compressible frax would compromise the integrity of the rivet.
I guess I'm missing something key here since I could ask the same question of all of the fuel fittings too. (Should the nut clamp down over the frax?) For things like my ammeter shunt my plan was to use a washer to shim the thing the width of the frax, cut out a small hole for the washer and then bolt the ammeter through the stainless. At least I've got that part straight.
Thanks for your help thinking this through, all! Can't wait to get this firewall shielded.
I've read everything I can find about insulating the firewall with Fiberfrax and stainless foil, and I'm attempting to follow best practices here, but there are a couple of details that I just haven't been able to glean from all of the incredible research out there. I have two questions.
First - are folks bolting the heater boxes directly to the firewall and then nesting the fiberfrax around it, OR bolting the heater boxes through the foil and fiberfrax? I get that the point of the fiberfrax is to insulate the firewall, and having the heater boxes directly contacting the firewall creates a bunch of heat transfer. BUT, the plans call for sealing the heater boxes, and my worry is that the compressible fiberfrax won't allow a solid seal.
Second, for the oil cooler mount, same sort of question. Are y'all riveting the cooler mount THROUGH the fiberfrax and foil, or, say, shimming it the width of the frax and then riveting through the stainless foil? The former seems ideal, but it feels like riveting through the compressible frax would compromise the integrity of the rivet.
I guess I'm missing something key here since I could ask the same question of all of the fuel fittings too. (Should the nut clamp down over the frax?) For things like my ammeter shunt my plan was to use a washer to shim the thing the width of the frax, cut out a small hole for the washer and then bolt the ammeter through the stainless. At least I've got that part straight.
Thanks for your help thinking this through, all! Can't wait to get this firewall shielded.